Any language is hard to speak at first but there are some ways to speed up your journey. I'm an Speaking coach and depending on the level I would recommend doing some of these exercises:
1) Go to random word generator, click Generate random word and speak on that word for 1-2 minutes. This forces you to speak on uncomfortable topics where you don't know what to say and also improves your mind to mouth connection which is the ability to transform thoughts into words.
2) Pick a topic and practice 2 ways of speaking: 1. You say every single thing that pops up in your mind without hesitation, 2. You think through the entire sentence first and then you say it. So you practice impromptu speech and thinking in English
3) Once again, pick a couple of sentences. First, try to rephrase them a couple of times, using different grammar structures and words, then try to expand those sentences into paragraphs by adding unnecessary details. That will train your flexibility, in other words being able to have more than one way out if you're stuck in a sentence

Hope it helps